Abstract: Aspects of the invention relate to methods and assemblies for improving the efficiency of a turbine engine through active management of blade tip clearances. In some designs, a portion of compressor exit air is routed to the rotor and discs of the turbine section. Aspects of the invention relate to treating the compressor exit air in light of the operating conditions of the engine. For instance, under base load or substantially steady state operation, a portion of compressor exit air can be routed to the rotor and discs without reducing the temperature of the compressor exit air. In such case, blade tip clearances will reduce, allowing for improved engine efficiency. Under part load or substantially transient operating conditions, a portion of compressor exit air can be cooled before it is supplied to the rotor and discs. As a result, the blade tip clearances increase, minimizing concerns of blade tip rubbing. Routing of the compressor exit air for cooling and bypass can be controlled by a valve.

Abstract: Aspects according to the invention relate to a catalytic combustor system for a turbine engine and an associated method. Catalytic combustors are used in connection with turbine engines because they can minimize the formation of oxides of nitrogen during combustion. Despite this emissions advantage, catalytic combustion systems can increase the level of CO in the turbine exhaust. According to aspects of the invention, vortex formation devices includes vortex generators, swirlers and mixers can be placed downstream of each catalytic module surrounding the pilot nozzle so as to form one or more vortices in the otherwise substantially laminar flow exiting the modules. The vortices can create a suction so that a portion of the flow exiting the pilot nozzles is mixed with the flow exiting the catalyst modules. The introduction of the higher temperature pilot flow can accelerate the catalytic reaction time, promoting burnout of the CO formed during combustion.

Abstract: A turbine vane for a turbine engine having a cooling system in inner aspects of the turbine vane. The cooling system includes one or more vortex forming chambers proximate to the intersection of an airfoil forming a portion of the turbine vane and an endwall to which the airfoil is attached. The intersection of the airfoil and the endwall may include a fillet for additional strength at the connection. The vortex forming chambers receive cooling fluids from cooling injection holes that provide a cooling fluid supply pathway between the cooling air supply cavity and the vortex forming chambers. The cooling fluids may be exhausted through one or more film cooling holes. The film cooling holes may exhaust cooling fluids proximate to the fillet to reduce the temperature of the external surface of the fillet and surrounding region.

Abstract: A method of manufacturing a composite structure uses a layer of an insulating material (22) as a mold for forming a substrate of a ceramic matrix composite (CMC) material (24). The insulating material may be formed in the shape of a cylinder (10) with the CMC material wound on an outer surface (14) of the cylinder to form a gas turbine combustor liner (20). Alternatively, the insulating material may be formed in the shape of an airfoil section (32) with the CMC material formed on an inside surface (36) of the insulating material. The airfoil section may be formed of a plurality of halves (42, 44) to facilitate the lay-up of the CMC material onto an easily accessible surface, with the halves then joined together to form the complete composite airfoil. In another embodiment, a box structure (102) defining a hot gas flow passage (98) is manufactured by forming insulating material in the shape of opposed airfoil halves (104) joined at respective opposed ends by platform members (109).

Abstract: An improved turbine spring clip seal for directing gases to be mixed with fuel in a combustor basket. The turbine spring clip seal is composed of inner and outer housings and a center sealing member disposed between the inner and outer housings. The center sealing member is flexible and prevents a fluid, such as air, from leaking through the seal. In operation, the center sealing member flexes and is sealed against the outer housing by a pressure differential that is created by the relatively higher pressure on the inner housing side and the relatively lower pressure on the outer housing side.

Abstract: A turbine vane usable in a turbine engine and having at least one cooling system. The cooling system includes a leading edge cavity and a trailing edge cavity. The cavities may be separated with a metering rib having one or more metering orifices for regulating flow of cooling fluids to a manifold cooling system and to trailing edge exhaust orifices. In at least one embodiment, the trailing edge cavity may be a serpentine cooling pathway and the leading edge cavity may include a plurality of leading edge cooling paths.

Abstract: A gas turbine engine (120) includes a cylindrical basket (146) having an axis (14) and a single main burner assembly (12) disposed within the basket. A burner insert (34) is disposed in an annular space between the burner assembly and the basket. The insert includes a face perpendicular to the axis of the basket. A plurality of passageways (114) are formed in the basket, positioned proximate to and downstream of the burner insert for allowing passage of a portion of an oxidizer flow (42) into a combustion chamber (30). A fluid flow path (38), defined between a combustion chamber liner portion (32) of the basket and a casing (40) spaced radially outward from the combustion liner portion, discharges a fluid into a flow reversal region (118) proximate an inlet (20) of the burner assembly. A fuel outlet (44) is disposed in the flow reversal region.

Abstract: A system (150) and method of tensioning a bolt (44) across a flange assembly (42). A tensioning apparatus (40) includes the bolt and an unthreaded nut (48) connected to the shank member by an interference fit. The interference fit may be selectively relaxed by applying a fluid pressure to a groove (54) between the nut and the bolt. A tensioner (58) is energized by a pressure to pre-load the bolt by pulling on the bolt while pushing on the nut while the interference fit is sufficiently relaxed to allow relative movement between the nut and the bolt. The tensioner is sized to achieve the required pre-load in the bolt at the same working fluid pressure that is necessary to relax the interference fit on the stretched bolt, thus permitting a single pressure source (148) to be used for both functions.

Abstract: A method of monitoring the condition of a thermal barrier coating on a turbine blade or vane during operation of the turbine is provided. The method includes providing a means for receiving acoustic output of the blade or vane during operation of the turbine and monitoring the acoustic output over time, to determine the condition of the thermal barrier coating on the blade or vane. The acoustic output arises from a force on the blade or vane, such as that due to impact of particles, a pulse of gas pressure or constant gas flow. An apparatus employing the above method for monitoring the condition of the thermal barrier coating during operation of the turbine, is also provided.

Abstract: A system for generating a sensor model for use in sensor-based monitoring is provided. The system includes a segmenting module for segmenting a collection of sensor vectors into a plurality of bins comprising distinct sensor vectors. The system also includes a set-generating module for generating a set of statistically significant sensor vectors for each bin. The system further includes a consistency determination module for generating at least one consistent set of sensor vectors from the sets of statistically significant sensor vectors. Additionally, the system includes a model-generating module for generating a sensor model based upon the at least one consistent set.

Abstract: A turbine blade for a turbine engine having at least one secondary flow deflector proximate to a blade tip for reducing the effective flow path between the blade tip and an adjacent outer seal. The turbine blade may be a superblade having a central opening forming a hollow turbine blade. The turbine blade may include a secondary flow deflector on upstream sides of the pressure side wall and the suction side wall. The downstream sides of the pressure and suction side walls may include chamfered corners. The secondary flow deflector reduces the effective flow path between the blade tip and an outer seal in numerous ways.

Abstract: A high temperature hydrogen gas separation membrane employing a physically interlocking barrier layer to form a spinel or intermetallic architecture bonding the metal barrier layer onto the surface of a fibrous metal medial structural support substrate. A tantalum/niobium interface layer is deposited on the barrier layer. The final layer is a precious metal such as palladium, which is deposited on the tantalum/niobium interface layer.

Abstract: A pressure sensor (52) for a harsh environment such as the combustion chamber (58) of a gas turbine engine (50). The pressure sensor includes an acoustic waveguide (60) having a sensing portion (66) exposed to the combustion gas in the combustion chamber. Modulations in an acoustic signal passing through the acoustic waveguide are sensed and correlated to pressure fluctuations in the combustion gas. The sensing portion of the waveguide includes a core acoustic waveguide element (42) covered by a coating material (44). The coating material not only protects the core from the harsh environment, but it also improves the efficiency of the transfer of energy from the combustion gas into the waveguide because it provides a stepped transition from the acoustic impedance of the gas to the acoustic impedance of the core material. The protective coating may have a plurality of layers (46, 48) and/or it may include a graded material (78, 80) having an acoustic impedance value that varies across its depth.

Abstract: A combustion turbine power plant (10) incorporating a desiccating scrubber (140) for simultaneously removing water and sulfur from a flue gas (20) of the power plant (10). The desiccating scrubber (140) may include an inlet nozzle (145) for spraying an aqueous solution (142) containing a desiccant and a base into flue gas (20) so the aqueous solution (142) makes direct contact with flue gas (20). A filter (162) may be provided to collect sulfur compounds downstream of the desiccating scrubber (140) and a regenerator (164) may be provided for recovering water. A controller (148) may control a base supply (170) and a desiccant supply (172) to regulate the respective amounts of each introduced into the aqueous solution (142). Controller (148) may be responsive to sensors (142) measuring the water and sulfur content of flue gas (20) exhausted to atmosphere (144). The desiccating scrubber (140) may include a demister (160) to entrain carryover droplets from a sprayed aqueous solution (142).

Abstract: Aspects of the invention relate to a system for reducing relative movement between the outer shroud of a compressor diaphragm and the compressor cylinder of a turbine engine, thereby minimizing the wearing of these parts. Embodiments of the invention include a system for applying an axial preload on the outer shroud of a compressor diaphragm, preferably in the same direction as the gas load in the compressor. The system can be installed at or near the horizontal joint such that the axial preload can be applied substantially at the horizontal joint, which is the location of the largest relative movement. In one embodiment, the axial preload system can include a two-piece wedge block and pin. As the pin is driven between the two wedge blocks, the force applied to the pin can be converted to an axial load by the spreading apart of the two wedge block sections.

Abstract: An improved method of heat treating superalloys prior to welding includes subjecting only the portion of the component to be repaired to a localized heat treatment, leaving the remainder of the component untreated. The localized heat treatment permits the use of higher hold temperatures that are near, at, or above the Ni3(Al,Ti) solution temperature of the alloy. Such heat treatment prevents strain age cracking and also prevents recrystallization in areas that are not heat treated. Such localized heat treatment can be applied before and/or after welding, for material rejuvenation, pre-brazing, and post-brazing.

Abstract: A method and apparatus for reducing steam swirl in a steam turbine. A plurality of seal segments (14) are circumferentially juxtaposed to form a seal ring (12) encircling the turbine shaft (10), each seal segment (14) supporting a plurality of circumferentially disposed annular seal fins (20) to limit axial steam flow along the shaft (10). A plurality of flow dams (40) are disposed within grooves (42) defined in the plurality of seal fins (20) and seal segments (14) for limiting circumferential steam flow and thereby reducing rotor instability.

Abstract: A support structure (20) is provided for supporting and spacing apart high-voltage electrical conductors (12) in an electric machine. An exemplary support structure (20) includes an improved spacer block (32,33) that is configured to reduce electrical flashover, in the form of creep, between adjacent high voltage conductors, without necessarily increasing the width of the spacer block. The improved spacer block (32,33) includes a main body (33) and a protruding portion (32), which elongates the creepage path (30) between adjacent high-voltage conductors to greater than the width of the spacer block (32,33).

Abstract: A joined assembly and kit for a rotor of a dynamoelectric machine are provided. The joined assembly is part of a conductive path generally extending from a radially inward section of the rotor to a radially outward section of the rotor. The conductive path includes a flexible connecting member from the radially inward section of the rotor to the joined assembly. The joined assembly includes a stacked winding energizable in response to excitation current carried by the conductive path to a top of the stacked winding located at the radially outward section of the rotor. The joined assembly further includes a connector with a first leg providing an electrically insulated mechanical point of contact relative to a bottom of the stacked winding.

Abstract: A xenotime phosphate protective overlayer (22) for protecting a ceramic material (24) from a high temperature, moisture-containing environment. Yttrium phosphate may be used as a protective overlayer to protect an underlying mullite layer to temperatures in excess of 1,500° C. The coating may have porosity of greater than 15% for improved thermal shock protection. To prevent the ingress of oxygen to an underlying ceramic non-oxide material, such as silicon carbide or silicon nitride, an oxygen barrier layer (34) is disposed between the xenotime phosphate coating and the non-oxide material. Such a protective overlayer may be used for an article having a ceramic matrix composite substrate.